1. Field of the Invention
This invention relates to an office machine, and more particularly to an automatic document feeder that allows for easy removal of jammed sheets of paper.
2. Description of the Related Art
Referring to FIG. 1, a conventional automatic document feeder includes a housing body 1, a top cover 101 disposed pivotally on the housing body 1, a feeding roller unit 2 disposed on the top cover 101, a conveying roller unit 3 disposed at a side of the feeding roller unit 2, an ejecting roller unit 4 disposed at an opposite side of the feeding roller unit 2, a driving unit 5 for driving the conveying roller unit 3, and a drive gear unit 6 driven by the driving unit 5. The driving unit 5 includes a motor 501 and a driving wheel 502 driven by the motor 501 to thereby rotate synchronously with the conveying roller unit 3. The drive gear unit 6 includes a first gear 601 driven by the driving wheel 502, a second gear 602 meshing with the first gear 601 for driving the feeding roller unit 2, a connecting rod 603 interconnecting the first and second gears 601, 602, a spring 604 for biasing the second gear 602 to pivot upwardly, and a third gear 605 meshing with the second gear 602 for driving the ejecting roller unit 4. When the top cover 101 is opened, the second gear 602 is biased by the spring 604 to pivot upwardly. Thus, the power connection between the driving unit 5 and the ejecting roller unit 4 is interrupted so as to allow a jammed sheet of paper to be removed from the ejecting roller unit 4. When the top cover 101 is closed, the second gear 602 is returned to the original position to thereby mesh with the third gear 605.
However, due to the power connection between the driving unit 5 and the conveying roller unit 3 during the opening of the top cover 101, a jammed sheet of paper cannot be removed from the conveying roller unit 3.